Ecology and the Environment - Biology Flashcards
Define the term population in ecology
A group of individuals of the same species living in a specific area
Population is a fundamental concept in ecology, representing the number of individuals of a species in a defined geographical area.
What is a community in ecological terms?
A collection of different species living together in a particular habitat
Communities include various populations that interact with one another.
Define habitat
The natural environment where an organism lives
Habitats provide the necessary resources for survival, such as food, water, and shelter.
What is an ecosystem?
A biological community of interacting organisms and their physical environment
Ecosystems include both biotic (living) and abiotic (non-living) components.
What is the purpose of using quadrats in ecological studies?
To investigate the population size of an organism in different areas
Quadrats are square plots used to sample and measure the abundance of species.
Define biodiversity
The variety of life in a particular habitat or ecosystem
Biodiversity encompasses the diversity of species, genetic variation, and ecosystem diversity.
How can biodiversity be measured?
By investigating the distribution of organisms in their habitats using quadrats
This involves counting species and assessing their abundance.
What are abiotic factors?
Non-living chemical and physical parts of the environment
Examples include temperature, water, soil, and light.
What are biotic factors?
Living components of the environment that affect organisms
Biotic factors include interactions such as predation, competition, and symbiosis.
What are the names of different trophic levels?
Producers, primary consumers, secondary consumers, tertiary consumers, decomposers
Each trophic level represents a step in the food chain.
What is a food chain?
A linear sequence of organisms through which nutrients and energy pass
Food chains illustrate how energy flows in an ecosystem.
What is a food web?
A complex network of interconnected food chains
Food webs show the multiple feeding relationships in an ecosystem.
What do pyramids of number represent?
The number of individual organisms at each trophic level
They visually depict the population size at different levels in a food chain.
What do pyramids of biomass indicate?
The total dry biomass at each trophic level
Biomass pyramids help understand energy transfer within ecosystems.
What do pyramids of energy transfer show?
The flow of energy through each trophic level in an ecosystem
Energy pyramids illustrate the decrease in energy available at higher trophic levels.
Why is only about 10% of energy transferred from one trophic level to the next?
Due to energy loss through metabolic processes and heat
This is known as the 10% rule in ecology.
Describe the stages in the carbon cycle
In the atmosphere (As CO2), absorbed by plants for photosynthesis, absorbed by animals that eat the plants, released back into the atmosphere through decomposition.
These stages illustrate how carbon moves through the ecosystem.
What roles do nitrogen-fixing bacteria play in the nitrogen cycle?
They convert atmospheric nitrogen into ammonia (NH4)
Nitrogen-fixing bacteria are essential for soil fertility.
What is the biological consequence of air pollution by sulfur dioxide?
Causes acid rain which leads to increased acidity of lakes, harming biodiversity. Aditionally, decreases soil pH which can denature enzymes in the roots of plants, reducing mineral uptake
Sulfur dioxide contributes to acid rain, affecting ecosystems.
List greenhouse gases
Water vapour, carbon dioxide, nitrous oxide, methane, CFCs
Greenhouse gases trap heat in the atmosphere, contributing to climate change.
How do human activities contribute to greenhouse gases?
Through burning fossil fuels, deforestation, and industrial processes
These activities release significant amounts of greenhouse gases into the atmosphere.
What is the enhanced greenhouse effect?
When too much heat is reflected back into the Earth’s surface due to an excess amount of greenhouse gases in the atmosphere. Causes global warming.
This effect results in climate change and associated environmental impacts.
What are the biological consequences of water pollution by sewage?
It can lead to eutrophication and harm aquatic life
Sewage introduces pathogens and nutrients that disrupt ecosystems.
What is eutrophication?
The enrichment of water bodies with nutrients leading to excessive plant growth
Eutrophication often results in oxygen depletion and harm to aquatic organisms.
What are the effects of deforestation?
Leaching, soil erosion, disturbance of evapotranspiration, and imbalance of atmospheric gases
Deforestation significantly impacts local and global ecosystems.
